xref: /llvm-project/llvm/test/Transforms/InstCombine/strncmp-6.ll (revision 90ba33099cbb17e7c159e9ebc5a512037db99d6d)
1; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
2; RUN: opt < %s -passes=instcombine -S | FileCheck %s
3;
4; Exercise folding of strncmp calls with constant arrays including both
5; negative and positive characters and both constant and nonconstant sizes.
6
7declare i32 @strncmp(ptr, ptr, i64)
8
9@a = constant [7 x i8] c"abcdef\7f"
10@b = constant [7 x i8] c"abcdef\80"
11
12
13; Exercise strncmp(A + C, B + C, 2) folding of small arrays that differ in
14; a character with the opposite sign and a constant size.
15
16define void @fold_strncmp_cst_cst(ptr %pcmp) {
17; CHECK-LABEL: @fold_strncmp_cst_cst(
18; CHECK-NEXT:    store i32 -1, ptr [[PCMP:%.*]], align 4
19; CHECK-NEXT:    [[SB5_A5:%.*]] = getelementptr i8, ptr [[PCMP]], i64 4
20; CHECK-NEXT:    store i32 1, ptr [[SB5_A5]], align 4
21; CHECK-NEXT:    [[SA6_B6:%.*]] = getelementptr i8, ptr [[PCMP]], i64 8
22; CHECK-NEXT:    store i32 -1, ptr [[SA6_B6]], align 4
23; CHECK-NEXT:    [[SB6_A6:%.*]] = getelementptr i8, ptr [[PCMP]], i64 12
24; CHECK-NEXT:    store i32 1, ptr [[SB6_A6]], align 4
25; CHECK-NEXT:    ret void
26;
27  %p5 = getelementptr [7 x i8], ptr @a, i64 0, i64 5
28  %p6 = getelementptr [7 x i8], ptr @a, i64 0, i64 6
29
30  %q5 = getelementptr [7 x i8], ptr @b, i64 0, i64 5
31  %q6 = getelementptr [7 x i8], ptr @b, i64 0, i64 6
32
33  ; Fold strncmp(a + 5, b + 5, 2) to -1.
34  %ca5_b5 = call i32 @strncmp(ptr %p5, ptr %q5, i64 2)
35  store i32 %ca5_b5, ptr %pcmp
36
37  ; Fold strncmp(b + 5, a + 5, 2) to +1.
38  %cb5_a5 = call i32 @strncmp(ptr %q5, ptr %p5, i64 2)
39  %sb5_a5 = getelementptr i32, ptr %pcmp, i64 1
40  store i32 %cb5_a5, ptr %sb5_a5
41
42  ; Fold strncmp(a + 6, b + 6, 1) to -1.
43  %ca6_b6 = call i32 @strncmp(ptr %p6, ptr %q6, i64 1)
44  %sa6_b6 = getelementptr i32, ptr %pcmp, i64 2
45  store i32 %ca6_b6, ptr %sa6_b6
46
47  ; Fold strncmp(b + 6, a + 6, 1) to  +1.
48  %cb6_a6 = call i32 @strncmp(ptr %q6, ptr %p6, i64 1)
49  %sb6_a6 = getelementptr i32, ptr %pcmp, i64 3
50  store i32 %cb6_a6, ptr %sb6_a6
51
52  ret void
53}
54
55
56; Exercise strncmp(A, B, N) folding of arrays that differ in a character
57; with the opposite sign and a variable size
58
59define void @fold_strncmp_cst_var(ptr %pcmp, i64 %n) {
60; CHECK-LABEL: @fold_strncmp_cst_var(
61; CHECK-NEXT:    [[TMP1:%.*]] = icmp ugt i64 [[N:%.*]], 6
62; CHECK-NEXT:    [[CA0_B0:%.*]] = sext i1 [[TMP1]] to i32
63; CHECK-NEXT:    store i32 [[CA0_B0]], ptr [[PCMP:%.*]], align 4
64; CHECK-NEXT:    [[TMP2:%.*]] = icmp ugt i64 [[N]], 6
65; CHECK-NEXT:    [[CB0_A0:%.*]] = zext i1 [[TMP2]] to i32
66; CHECK-NEXT:    [[SB0_A0:%.*]] = getelementptr i8, ptr [[PCMP]], i64 4
67; CHECK-NEXT:    store i32 [[CB0_A0]], ptr [[SB0_A0]], align 4
68; CHECK-NEXT:    [[TMP3:%.*]] = icmp ne i64 [[N]], 0
69; CHECK-NEXT:    [[CA6_B6:%.*]] = sext i1 [[TMP3]] to i32
70; CHECK-NEXT:    [[SA6_B6:%.*]] = getelementptr i8, ptr [[PCMP]], i64 8
71; CHECK-NEXT:    store i32 [[CA6_B6]], ptr [[SA6_B6]], align 4
72; CHECK-NEXT:    [[TMP4:%.*]] = icmp ne i64 [[N]], 0
73; CHECK-NEXT:    [[CB6_A6:%.*]] = zext i1 [[TMP4]] to i32
74; CHECK-NEXT:    [[SB6_A6:%.*]] = getelementptr i8, ptr [[PCMP]], i64 12
75; CHECK-NEXT:    store i32 [[CB6_A6]], ptr [[SB6_A6]], align 4
76; CHECK-NEXT:    ret void
77;
78  %p6 = getelementptr [7 x i8], ptr @a, i64 0, i64 6
79
80  %q6 = getelementptr [7 x i8], ptr @b, i64 0, i64 6
81
82  ; Fold strncmp(a, b, n) to -1.
83  %ca0_b0 = call i32 @strncmp(ptr @a, ptr @b, i64 %n)
84  store i32 %ca0_b0, ptr %pcmp
85
86  ; Fold strncmp(b, a, n) to +1.
87  %cb0_a0 = call i32 @strncmp(ptr @b, ptr @a, i64 %n)
88  %sb0_a0 = getelementptr i32, ptr %pcmp, i64 1
89  store i32 %cb0_a0, ptr %sb0_a0
90
91  ; Fold strncmp(a + 6, b + 6, n) to -1.
92  %ca6_b6 = call i32 @strncmp(ptr %p6, ptr %q6, i64 %n)
93  %sa6_b6 = getelementptr i32, ptr %pcmp, i64 2
94  store i32 %ca6_b6, ptr %sa6_b6
95
96  ; Fold strncmp(b + 6, a + 6, n) to +1.
97  %cb6_a6 = call i32 @strncmp(ptr %q6, ptr %p6, i64 %n)
98  %sb6_a6 = getelementptr i32, ptr %pcmp, i64 3
99  store i32 %cb6_a6, ptr %sb6_a6
100
101  ret void
102}
103